Dissociation Dynamics of Doubly and Triply Charged Simple Gaseous Molecules Studied by Double and Triple Coincidence Method

双重合和三重符合法研究双重和三重简单气态分子的离解动力学

• 批准号: 01540383
• 负责人: MASUOKA Toshio
• 金额: $ 0.9万
• 依托单位: Osaka City University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1989
• 资助国家: 日本
• 起止时间: 1989 至 1990
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-01540383/
• 关键词: Double ionization; Dissociative photoionization; Ionic fragment; Anisotropy of fragmentation; Kinetic energy distribution; Triple coincidence; Synchrotron radiation

1. The triple coincidence PEPIPICO (photo electron-photoion-photoion) technique has been developed at the UVSOR facility of IMS (BL3A2) in Okazaki to study the dynamics of fragmentations of a di-or tri-cation into two charged and one neutral particle. Two dimensional expression of the triple coincidence spectra in real time was made possible by use of a personal computer and a video RAM. The dissociative double and triple photoionization of OCS was studied by this method at the excitation energy of 80eV. New information on the charge separation was obtained for the dissociation channels C^++ O^++S of OCS^<2+> and OC^++S^<2+> of OCS^<3+>.2. The angular distribution of photo dissociation products is closely related to the symmetry of the transition processes involved and the molecular dissociation dynamics. We have observed angular distribution of fragment ions produced in the direct (not via Auger decay) double photoionization of OCS, CH_3F, and NO by use of synchrotron radiation and the photoion-photoion coincidence (PIPICO) method. The TOF mass spectrometer could be rotated throuqh 90^ﾟ around the photon beam in order to measure characteristic profiles of the PIPICO spectra. The present study shows that the anisotropy, observed here for the first time in the case of direct two-electron-ejection processes, can be understood in terms of symmetry-characterized-dissociation of the doubly charged parent ions.3. The single, double, and triple photoionization cross sections of OCS and the ionic fragmentations of OCS^+, OCS^<2+>, and OCS^<3+> have been determined separately in the region 36-100eV by use of a TOF mass spectrometer and the PIPICO method together with synchrotron radiation from the UVSOR4. Kinetic energy distributions of the fragment ions produced from OCS^<2+> and NO^<2+> were also determined.

1.三重符合PEPIPICO（光电子-光离子-光离子）技术已在冈崎IMS（BL 3A 2）的UVSOR设施开发，以研究二或三阳离子碎裂成两个带电粒子和一个中性粒子的动力学。利用个人计算机和视频存储器实现了三重符合谱的真实的二维表示。在激发能为80 eV的条件下，用该方法研究了OCS分子的解离二次和三次光电离。对OCS^<2+>的解离通道C^++ O^++S和OCS^<3+>的解离通道OC^++S^<2+>获得了电荷分离的新信息。光解产物的角分布与跃迁过程的对称性和分子解离动力学密切相关。利用同步辐射和光离子-光离子符合（PIPICO）方法，观察了OCS、CH_3F和NO直接（不通过俄歇衰变）双光电离产生的碎片离子的角分布。TOF质谱仪可以围绕光子束旋转90 °/h，以测量PIPICO光谱的特征曲线。本研究表明，在直接双电子喷射过程中首次观察到的各向异性，可以用双电荷母离子的解离来理解.用飞行时间质谱仪和PIPICO方法，结合UVSOR 4同步辐射，分别测定了OCS在36- 100 eV范围内的单、双、三重光电离截面和OCS^+、OCS^<2+>、OCS^<3+>的离子碎裂截面。还测定了OCS^<2+>和NO^<2+>产生碎片离子的动能分布.

项目成果

T. Masuoka: "Construction of a new apparatus for angle and energy resolved measurements of photoelectrons and photoions" Rev. Sci. Instrum. 60. 2179-2181 (1989)

T. Masuoka：“构建用于光电子和光子的角度和能量分辨测量的新装置”Rev. Sci。

T.Masuoka: "Anisotropic angular distribution of fragment ions in dissociative double photoionization of CH_3F" J.Phys.B.

T.Masuoka：“CH_3F 解离双光电离中碎片离子的各向异性角分布”J.Phys.B。

T.Masuoka: "Dissociative single,double,and triple photoionization of OCS in the region hv=20ー100eV studied by mass spectrometry and photoionーphotoion coincidence method" J.Chem.Phys.

T.Masuoka：“通过质谱和光离子符合法研究OCS在hv=20－100eV区域的单、双和三重光电离” J.Chem.Phys。

S.Nagaoka: "Dissociative photoionization of Al_2(CH_3)_6 and Al_2(CH_3)_3Cl_3 in the range 40ー100eV" Appl.Organomet.Chem.

S.Nagaoka：“Al_2(CH_3)_6和Al_2(CH_3)_3Cl_3在40－100eV范围内的离解光电离”​​Appl.Organomet.Chem。

S. Nagaoka: "Dissociative photoionization of Al_2(CH_3)_6 and Al_2(CH_3)_3 Cl_3 in the range 40-100eV" Appl. Organomet. Chem.

S. Nagaoka：“Al_2(CH_3)_6 和 Al_2(CH_3)_3 Cl_3 在 40-100eV 范围内的离解光电离”Appl。